Earthquake · reviewed by a seismologist
M 3.8mw
0km NNW of The Geysers, CA
- When
- Magnitude
- M 3.8 (mw)
- Depth
- 0.4 km below the surface
- Felt
- 33 reports · strongest reported intensity IV
- Measured shaking
- intensity V (ShakeMap)
- Nearest
- Sonoma County, 32 km SSW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1604 days ago
This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 33 people have reported feeling it to USGS.
How big was it?
This earthquake released about 7.1 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.8 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 24,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 1,100× the energy of this one
- Magna, Utah 2020 M 5.7 760× the energy of this one
- This earthquake M 3.8 about 7.1 tons of TNT
- Around the size people start to feel M 3.0 this one released 15× more
Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.
Where
Epicentre 38.7805, -122.7582. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| Sonoma County, CA | 32 km (20 mi) | NNE of here | earthquakes near Sonoma County |
| Lake County, CA | 36 km (23 mi) | S of here | earthquakes near Lake County |
| Napa County, CA | 48 km (30 mi) | NW of here | earthquakes near Napa County |
| Colusa County, CA | 63 km (39 mi) | SW of here | earthquakes near Colusa County |
| Yolo County, CA | 75 km (47 mi) | W of here | earthquakes near Yolo County |
| Marin County, CA | 81 km (50 mi) | N of here | earthquakes near Marin County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
60 earthquakes have been recorded within 50 km since this one.
- 2.5 7km NW of The Geysers, CA
- 1.6 8km ENE of Healdsburg, CA
- 1.5 4km W of Cobb, CA
- 1.8 3km NE of The Geysers, CA
- 1.9 5km WNW of The Geysers, CA
- 2.7 4km NW of The Geysers, CA
- 1.7 2km WSW of Anderson Springs, CA
- 1.6 5km WNW of The Geysers, CA
- 1.7 6km NW of The Geysers, CA
- 2.2 3km SE of The Geysers, CA
- 1.7 7km WNW of The Geysers, CA
- 1.8 7km WNW of The Geysers, CA
- 2.1 5km WSW of Kenwood, CA
- 2.0 7km NW of The Geysers, CA
- 1.6 7km NW of The Geysers, CA
Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.
For this area
The largest earthquake within 50 km in our catalogue was M 5.0 on 2016-12-14 — it released about 70 times the energy of this one.
From the QuakeIndex catalogue, built from the USGS FDSN event service.
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.